It is amazing that, even with a relatively simple brain, bumblebees are able to make such complex energetic decisions. Earlier studies on bumblebee foraging currencies had been primarily observational, making it difficult to distinguish bumblebees’ critical currency. Their decisions fit with a model in which their critical currency is the rate of energy return as opposed to energetic efficiency (minimising the amount of energy spent for any energy gained during foraging), the researchers report. By better understanding how foraging energetics influences their choices on which flowers to visit, this can help inform decisions on how bumblebees are used to pollinate crops. Resolving the currency through which bumblebees make their foraging decisions is one additional piece of this complex story.’The study ‘Bumblebees negotiate a trade-off between nectar quality and floral biomechanics’ has been published in iScience.